I had a custom stock on an LC Smith with straight grip bent by Steven Bertram 2-3 years ago.
http://www.bertramandco.com/ (303) 938-1996
He did not mess the finish or bottom tang up in any way and the gun was bent to my dimensions. The price for a single bend was $250 plus HIS. He was able to determine if my stock was a good candidate for bending via some pictures I sent him.